#include<bits/stdc++.h>
using namespace std;
const int N = 3e5 + 5;
const long long mod = 1e9 + 7;
int n;
long long arr[N];
int segtree[2 * N];
long merge(long x, long y){
return x + y;
}
void segtree_update(int ind, int val, int n_){
for(segtree[ind += n_] += val; ind > 1; ind >>= 1)
segtree[ind >> 1] = merge(segtree[ind], segtree[ind ^ 1]);
}
long segtree_query(int l, int r, int n_){
long res = 0;
for(l += n_, r += n_; l < r; l >>= 1, r >>= 1){
if((l & 1) == 1)
res = merge(res, segtree[l++]);
if((r & 1) == 1)
res = merge(res, segtree[--r]);
}
return res;
}
void solve(int test){
set<long long> s;
int i = 0;
for(i = 0; i < n; i++)
s.insert(arr[i]);
map<long long, int> mp;
int x = 0;
for(long long xx : s)
mp[xx] = x++;
vector<int> cnt(n);
int n_ = s.size();
for(i = 0; i < n; i++){
//cout <<
cnt[i] = segtree_query(0, mp[arr[i]], n_);
segtree_update(mp[arr[i]], 1, n_);
}
memset(segtree, 0, sizeof(segtree));
long long ans = 0;
for(i = n - 1; i >= 0; i--){
ans += cnt[i] * 1LL * segtree_query(0, mp[arr[i]], n_);
segtree_update(mp[arr[i]], 1, n_);
}
cout << ans << "\n";
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int t = 1;
//cin >> t;
for(int test = 1; test <= t; test++){
int i = 0;
cin >> n;
for(i = 0; i < n; i++)
cin >> arr[i];
solve(test);
}
return 0;
}
